Electronic tube



H. F. ELLIOTT ELECTRONIC TUBE Filed April 14, 1932 INVENTOjR Ham/d 22? Elliott BY HIS ATTORNEY Patented July 27, 1937 UNITED STATES PATENT oFFieE 25 Claims.

This invention relates to improvements in electronic tubes such as are used for amplifying, detecting and controlling signals in carrier wave communication and other purposes. An object of my invention is to provide means whereby the functions of amplifying, detecting and controlling carrier wave signals may be carried out more effectively than in methods heretofore in use. Another object is to provide means whereby a single tube of simple structure may be used to rectify and amplify carrier wave signals, and at the same time provide means of controlling amplification so that the effects of fading may be minimized and over-loading avoided. Another object is to provide means whereby devices for receiving carrier wave signals, such as broadcast receivers may be simplified and reduced in size and cost.

The tubes described and claimed hereinafter may be adopted to these purposes by the use of circuits described in my co-pending applications Serial Nos. 605,185, filed April 14, 1932; 606,612, filed April 21, 1932; 606,613, filed April 21, 1932; 607,857, filed April 2'7, 1932; 616,586, filed June 11, 1932; 628,629, filed Aug. 13, 1932.

Referring to the drawing:

Figs. 1, 2 and 3 show three forms which tubes constructed in accordance with my invention may take.

The tube in Fig. 1 comprises a cathode 2 of the uni-potential type, a main anode 6, an auxiliary anode l2 and two control grids 8 and 9, which are interposed symmetrically in the space between the cathode 2 and the main anode 6, but are not related to the auxiliary anode I 2. The cathode 2 may be connected through the lead 3 to one of the prongs M3 on the base [9. The cathode may be provided with a suitable heater 4 for raising its temperature to the proper point for the emission of electrons, and this heater may be connected by leads 5, 5 to suitable terminals on the base. The two control grids may likewise be connected through leads l and. II to suitable terminals on the base. The auxiliary anode l2 may be connected either to a terminal on the base or to a cap 20 on the top of the tube through the medium of lead l3, as shown in the figure. For purposes of clarity, no effort has been made to show mechanical details such as the supporting means for the various electrodes, but a relative arrangement and proportion is indicated of electrodes wherein the auxiliary anode is of less size normal to the cathode than the main anode. Furthermore the showing is illustrative of the cathode and the auxiliary anode as establishing a flow path with the electronic discharge to the auxiliary anode otherwise separate from the other electrodes. There is accordingly no appreciable influence or electronic relation of cathode-auxiliary anode with other electrodes. 2

In operation there are a great variety of ways in which the elements of tube of Fig. 1 may be utilized to advantage. Since circuits and connections for the use of the tube are described and claimed in separate applications, no discussion of these will be given here. It will be evident to those skilled in the communications art that the grids 6 and 9 may be used in various ways to control the flow of electrons from the cathode 2 to the main anode 6. It will also be evident that'the auxiliary anode [2 may be used to receive electrons from the cathode without material influence of the grids 8 and 9 and without material influence upon the flow of electrons between the other elements of the tube. These factors make it possible to employ the tube for Wide range of purposes, including detection, amplification, rectification, automatic control of volume and other useful purposes in electronic apparatus.

The tube in Fig. 2 is similar to the tube of Fig. 1 with theexception that a screen grid I 4 is interposed between the control grids and the main anode. The screen may be connected to a suitable terminal on the base through the medium of lead i5. Tubes having screens are now in Wide use commercially, and there is no need to describe the functions of such screens here beyond saying that through suitable proportions of the various tube elements, screens may be used to give tubes desired electrical characteristics, and also when desired, to prevent electrical interactions between tube elements and circuits connected thereto.

The tube of Fig. 3 is similar to the tube of Fig. 2 except that two screens are provided in place of one. The second is designated by numeral l6 and its connection by numeral ll. As

is now well understood in connection with standard commercial tubes of the so-called pentode type, double screens of the sort shown are useful in controlling the electrical characteristics of tubes and preventing interaction between tube elements and circuits connected thereto.

What I claim is:

1. An electron tube having a main anode, a cathode having an extension beyond the end level of said main anode, an auxiliary anode adjacent said extension and more closely related to the cathode extension than the relation of the main anode to the cathode, said auxiliary anode being physically and electronically related to the cathode extension but effectively separated electronically from all other electrodes in the tube, and means for controlling the flow of electrons between the cathode and the main anode without appreciably influencing and without being appreciably influenced by the flow of electrons to the auxiliary anode, whereby said tube may function both as a demodulator and as a governor.

2. An electron tube having a main anode, a cathode having an extension beyond the end level of said main anode, control means interposed between the cathode and said main anode, and an auxiliary anode surrounding said extension and of less area than and more closely related physically to said extension than the relation of the main anode to the cathode and arranged to receive electrons from the cathode without appreciable influence of any control means and without appreciably influencing the flow of electrons to the main anode, whereby said tube may function both as a demodulator and as a governor.

3. An electron tube having a main anode, a cathode having an extension beyond the end level of said main anode, two control grids symmetrically arranged between the cathode and the main anode and terminating substantially at the end level of the anode, and an auxiliary anode beyond said end level of the first said main anode and grids and adapted to receive electrons from said extension of the cathode without appreciably influencing and without being appreciably influenced by the flow of electrons between other electrodes, whereby said tube may function both as a demodulator and governor.

4. An electron tube having a main anode, a cathode having an extension beyond the end level of said main anode, an auxiliary anode of smaller diameter than the main anode surrounding said extension, a plurality of intermeshed control grids between the main anode and cathode terminating substantially at the end level of the anode, said auxiliary anode being electronically related to the cathode extension but without appreciable electronic inter-relation with the other electrodes, whereby said tube may function both as a demodulator and governor.

5. An electron tube comprising an extended cathode, a main anode, an auxiliary anode, and a plurality of alternately spaced control grids between the cathode and the main anode, the said auxiliary anode being of less area than and closer to the cathode than the main anode and electronically related to the cathode extension without appreciable electronic relation to any other electrode, the said auxiliary anode being electronically related to the cathode extension and without appreciable electronic relation to any other electrode.

6. A tube in accordance with claim 1 with the addition of a screen grid between the cathode and main anode.

7. A tube in accordance with claim 2 with the addition of a screen grid between the cathode and main anode.

8. A tube in accordance with claim 3 with the addition of a screen grid between the control grids and main anode.

9. A tube in accordance with claim 4 with the addition of a screen grid between the control grids and main anode.

10. A tube in accordance with claim 1 with the addition of a plurality of auxiliary grids between the cathode and main anode.

11. A tube in accordance with claim 2 with the addition of a plurality of auxiliary grids comprising a screen and a suppressor between the cathode and main anode.

12. A tube in accordance with claim 3 with the addition of a plurality of auxiliary grids comprising an accelerator, a screen and a suppressor between the cathode and main anode.

13. A tube in accordance with claim 4 with the addition of a plurality of auxiliary grids between the cathode and main anode.

14. An electron discharge device comprising an extended unipotential cathode, control means and two anodes only one of which is inter-related with control means and one of which is physically closer to the cathode than the other, whereby said tube may function both as a demodulator and governor.

15. An electron discharge tube comprising an xtended unipotential cathode, two grids and two anodes only one of which is electrically interrelated with grids, any grids in said tubes, one of said anodes being physically closer to the cathode than the other, whereby said tube may function both as a demodulator and governor.

16. A modulator comprising an electron tube having an extended cathode, a main anode, control means for influencing the flow of electrons from the cathode to the anode, and an auxiliary anode of less area than and closer to the cathode than the main anode and arranged to receive electrons from the cathode extension not influenced by control means.

17. A modulator comprising an electron tube having an extended unipotential cathode, a main anode, two inter-meshing control grids, and an auxiliary anode of less area than and closer to the cathode than the main anode and electronically related to the cathode extension only.

18. A modulator comprising an extended unipotential cathode, a main anode, multiple symmetrically arranged control means cooperating therewith, and an auxiliary anode of less area than and closer to the cathode than the main anode and arranged to receive electrons from the cathode extension but electrically unrelated to other electrodes.

19. An electron tube having an extended cathode, a main anode, control means for influencing the flow of electrons from the cathode to the anode, and an auxiliary anode spaced longitudinally of the cathode substantially equi-distant from the adjacent ends of the main cathode and control means, and arranged to receive electrons from the cathode extension not appreciably influenced by control means.

20. An electron tube having an extended unipotential cathode, an anode, two intermeshing control grids, and an auxiliary anode spaced longitudinally of the cathode substantially equi-distant from the adjacent ends of the main cathode and grids and electronically related to the cathode extension without appreciable electronic interrelationship with. other electrodes.

21. An electron tube comprising an extended unipotential cathode, a main anode, multiple symmetrically arranged control means cooperating therewith, and an auxiliary spaced longitudinally of the cathode substantially equi-distant from the adjacent ends' of the main cathode and control means, and anode arranged to receive electrons from the cathode extension but without appreciable relationship electrically to other electrodes.

22. In combination in an electron tube, a unipotential cathode, a main anode surrounding one end of the cathode, an auxiliary anode surrounding the other end of the cathode and closer thereto than the main cathode, means for producing separate electron streams to the two anodes and means for controlling the electron stream from the cathode. to the main anode Without appreciably influencing the electron stream to the auxiliary or Without being appreciably influenced thereby.

23. In combination in an electron tube, an indirectly heated unipotential cathode, a main anode and at least one grid surrounding one end of said cathode, an auxiliary anode closely surrounding the other end of said cathode separated and physically separated substantially equi-distant from the main anode and grid structure and Without appreciable electronic influence from or upon said grid structure.

24. An electron tube of the pentode type having a group of pentode elements, a unipotential cathode extending beyond the end level of the said group of pentode elements, with at least one auxiliary anode of less area than and closer to the cathode than the anode of the said pentode group adjacent the extended portion of the cathode and receiving electrons therefrom without appreciable interaction with the electrons to electrodes of said group.

25. An electron tube of the screen grid type having a main section and an auxiliary section, the main section comprising a unipotential cathode and cold electrodes comprising a screen grid tube structure, the auxiliary section comprising, an extension or" the cathode and at least one cold electrode of less area and closer to the cathode than the main anode adjacent said extension and comprising therewith a loW impedance diode, with means for setting up separate electron streams in the main and auxiliary sections.

HARQLD F. ELLIOTT. 

